Artboard 2 copy 35Artboard 64 copy 13Artboard 2 copy 19Artboard 2 copy 31Artboard 64 copy 18Artboard 64 copy 10Artboard 64 copy 11Artboard 64 copy 15Artboard 64 copy 12Artboard 64 copy 13Artboard 64 copy 14Artboard 2 copy 34Artboard 64 copy 19Artboard 64 copy 16MinusArtboard 2 copy 44Artboard 2 copy 38Artboard 2 copy 36PlusArtboard 64 copy 17Artboard 2 copy 43Artboard 2 copy 45Artboard 2 copy 46Artboard 64 copy 16Artboard 64 copy 18Artboard 64 copy 19Artboard 64 copy 17

Sensory irritation of vapours of formic, acetic, propionic and butyric acid

Tidsskriftartikel - 2018

Resume

In mice, inhalation of formic, acetic, propionic and butyric acid caused a rapid decrease in the respiratory rate, which decreased to a stable level during the remaining part of the 30 min exposure period; this was due to sensory irritation. The concentration decreasing the respiratory rate (RD) by 50% (RD50) was 438, 308, 386 and 285 ppm, respectively, which allowed an adequate prediction of the Threshold Limit Values. In mice inhaling through a tracheal cannula, bypassing the trigeminal nerves, caused a slower decrease in respiratory rate due to pulmonary irritation. In the low concentration range, the pulmonary irritation response was less pronounced than the sensory irritation response. As the response in the normal (non-cannulated) mice was not influenced by pulmonary irritation, sensory irritation is the key effect, presumably due to the scrubbing effect of the upper airways, preventing access to the lungs. The activated receptors were in a non-lipophilic (hydrophilic) environment, from where the receptors may be activated by means of liberated protons. At the RD0, formic acid may, at least partly, activates ASIC, TRPV1 and TRPA1 receptors, whereas acetic, propionic and butyric acid may activate ASIC and TRPA1 receptors, based on the estimated pH in the mucus layer.

Reference

Nielsen GD. Sensory irritation of vapours of formic, acetic, propionic and butyric acid. Regulatory Toxicology and Pharmacology 2018;99:89-97.
doi: 10.1016/j.yrtph.2018.09.012

Gå til Tidsskriftartikel